package org.bouncycastle.asn1.pkcs;

import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.ASN1Set;
import org.bouncycastle.asn1.DEREncodable;
import org.bouncycastle.asn1.DERInteger;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.DERTaggedObject;
import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
import org.bouncycastle.asn1.x509.X509Name;

/**
 * PKCS10 CertificationRequestInfo object.
 * 
 * <pre>
 *  CertificationRequestInfo ::= SEQUENCE {
 *   version             INTEGER { v1(0) } (v1,...),
 *   subject             Name,
 *   subjectPKInfo   SubjectPublicKeyInfo{{ PKInfoAlgorithms }},
 *   attributes          [0] Attributes{{ CRIAttributes }}
 *  }
 * 
 *  Attributes { ATTRIBUTE:IOSet } ::= SET OF Attribute{{ IOSet }}
 * 
 *  Attribute { ATTRIBUTE:IOSet } ::= SEQUENCE {
 *    type    ATTRIBUTE.&id({IOSet}),
 *    values  SET SIZE(1..MAX) OF ATTRIBUTE.&Type({IOSet}{\@type})
 *  }
 * </pre>
 */
public class CertificationRequestInfo implements DEREncodable {
    DERInteger version = new DERInteger(0);
    X509Name subject;
    SubjectPublicKeyInfo subjectPKInfo;
    ASN1Set attributes = null;

    public static CertificationRequestInfo getInstance(Object obj) {
        if (obj instanceof CertificationRequestInfo) {
            return (CertificationRequestInfo) obj;
        } else if (obj instanceof ASN1Sequence) {
            return new CertificationRequestInfo((ASN1Sequence) obj);
        }

        throw new IllegalArgumentException("unknown object in factory");
    }

    public CertificationRequestInfo(X509Name subject, SubjectPublicKeyInfo pkInfo, ASN1Set attributes) {
        this.subject = subject;
        this.subjectPKInfo = pkInfo;
        this.attributes = attributes;

        if ((subject == null) || (version == null) || (subjectPKInfo == null)) {
            throw new IllegalArgumentException("Not all mandatory fields set in CertificationRequestInfo generator.");
        }
    }

    public CertificationRequestInfo(ASN1Sequence seq) {
        version = (DERInteger) seq.getObjectAt(0);

        subject = X509Name.getInstance(seq.getObjectAt(1));
        subjectPKInfo = SubjectPublicKeyInfo.getInstance(seq.getObjectAt(2));

        //
        // some CertificationRequestInfo objects seem to treat this field
        // as optional.
        //
        if (seq.size() > 3) {
            DERTaggedObject tagobj = (DERTaggedObject) seq.getObjectAt(3);
            attributes = ASN1Set.getInstance(tagobj, false);
        }

        if ((subject == null) || (version == null) || (subjectPKInfo == null)) {
            throw new IllegalArgumentException("Not all mandatory fields set in CertificationRequestInfo generator.");
        }
    }

    public DERInteger getVersion() {
        return version;
    }

    public X509Name getSubject() {
        return subject;
    }

    public SubjectPublicKeyInfo getSubjectPublicKeyInfo() {
        return subjectPKInfo;
    }

    public ASN1Set getAttributes() {
        return attributes;
    }

    public DERObject getDERObject() {
        ASN1EncodableVector v = new ASN1EncodableVector();

        v.add(version);
        v.add(subject);
        v.add(subjectPKInfo);

        if (attributes != null) {
            v.add(new DERTaggedObject(false, 0, attributes));
        }

        return new DERSequence(v);
    }
}
